Neil Rutter is one of the UK's most successful athletes, with three world titles to his name - yet hardly anyone has heard of him.
Mr Rutter is the world champion of the very unusual sport of bog snorkelling.
For the past three years the art teacher, from Swindon, Wiltshire, has propelled himself to victory along a narrow channel of filthy water 60 yards long.
Scores of people make the pilgrimage to Llanwrtyd Wells in mid-Wales each year to take on the challenge.
Daredevils don flippers, wetsuits, masks and snorkels before plunging in and swimming two lengths of the squalid trench.
But none of them come close to matching Mr Rutter's times in this uniquely British competition.
"Bog snorkelling is completely bonkers, it's just completely nuts.
"You're swimming through mud and the atmosphere's hilarious and everyone has a great time," he told BBC Inside Out West.
"You'll be bumping into the reeds and the muddy edges of the bog, and if you stand in it your feet sink into this disconcerting squelchy mess.
"Your mind will conjure up all sorts. So you'll be like: was that an eel? Do we have eels in bogs?"
Despite these trials, Mr Rutter made sure he defended his bog snorkelling title at the world championships in August.
"I love things that are a little bit daft," he said.
"I like the crazy stuff, anything that's a bit quirky captures my imagination."
But becoming a champion in any sport has its drawbacks.
"I'm in serious danger that it may actually define me," he said.
"I've done a lot of properly athletic endeavours in my life but all of it has been instantly overshadowed by bog snorkelling."
He faced stiff competition this year, not just from a cadre of competitors in fancy dress - including one in her own wedding dress from 20 years ago - but also his mother Julie.
Before the race he said everyone would be "gunning for him" and his enviable world record.
Fortunately his mother's fervent desire to keep her head out of the stagnant water meant she never threatened her son's world record of one minute 18 seconds.